Hide report from Print menu

Hide report from print menu via XML by setting binding_model_id.

<report id="report_contract_ad" model="custom_module.your_model"
        string="Custom report" report_type="qweb-pdf"
        name="custom_module.contract_ad"
        file="custom_module.contract_ad"
        print_report_name="str(time.strftime('%Y-%m-%d_%H-%M')) + '_contract_' + object.id"/>

<record id="report_contract_ad" model="ir.actions.report">
    <!-- Don't put it in Print menu -->
    <field name="binding_model_id"></field>
</record>